What is VAX (Virtual Address eXtension)? - Definition from WhatIs.com


VAX (Virtual Address eXtension)

Part of the Hardware glossary:

VAX (Virtual Address eXtension) is an established line of mid-range server computers from the Digital Equipment Corporation (DEC). It followed DEC's PDP-11 in 1978 and also introduced a new operating system, VMS. VAX included a 32-bit processor and virtual memory. Historically, VAX has competed with a number of Hewlett-Packard and IBM computers in the small enterprise and university-scientific marketplace. In earlier times, this size and price range of computer was known as the minicomputer. Today, VAX and its competitors sell "servers" for business networks that use the client/server computing model.

DEC indicates that over 250,000 VAX systems are in use. As of October, 1996, models were in the $18,000 to 46,000 price range. Based on VMS, its operating system is called OpenVMS. Among other features, OpenVMS can be used with special software that facilitates its use with Windows NT servers. OpenVMS also supports the open standard Portable Operating System Interface set of commands and C language programming interface, effectively making it both a VMS system and a UNIX system.

Eric S. Raymond notes that the VAX running a BSD Unix system was a favorite of hackers for its especially large and programmer-friendly set of assembler instructions.

This was last updated in March 2011
Posted by: Margaret Rouse

Related Terms


  • laser

    - A laser is a coherent and focused beam of photons; coherent, in this context, means that it is all one wavelength, unlike ordinary light which showers on us in many wavelengths. The acronym laser s... (WhatIs.com)

  • hardware virtualization

    - Hardware virtualization is the abstraction of computing resources from the software that uses those resources. Today, hardware virtualization is often called server virtualization or, simply, virtu... (SearchVMware.com)

  • robotics

    - Robotics is a branch of engineering that involves the conception, design, manufacture, and operation of robots. (WhatIs.com)


  • Hardware

    - Terms related to computer hardware, including definitions about cables, connectors and power supply units and words and phrases about computing peripheral devices including the keyboard, mouse, au...

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question About VAX (Virtual Address eXtension)Powered by ITKnowledgeExchange.com

Get answers from your peers on your most technical challenges

Tech TalkComment



    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.